Non-glycosylated protein, containing 72 amino acids, with a molecular weight of 8.5 kDa. Purity is typically 97% as determined by HPLC, reducing and non-reducing SDS-PAGE, UV spectroscopy at 280 nm. Stromal cell-derived factor-1 beta (SDF-1b), also called CXCL12b, is one of two SDF-1 splice variants made by a wide variety of cells upon stimulation by inflammatory cytokines such as TNF, IL-1, and LPS. SDF-1b signals through the G protein-coupled receptor CXCR4 to recruit activated leukocytes.